Windows Media Player cannot play this DVD because a compatible DVD decoder is not installed on your computer.
You load a DVD into your computer expecting it to launch in Windows Media Player but instead you get and error stating that “Windows Media Player cannot play this DVD because a compatible DVD decoder is not installed on your computer.” What is a DVD decoder and how do you get one?
To fit full length feature movies onto a DVD the video has to be compressed, and MPEG-2 is the industry standard compression for DVDs. The DVD decoder specified in the error is actually an MPEG-2 compliant decoder. Windows Media Player 11 does not come with a DVD decoder. You will have to add one to allow Windows Media Player to decompress the video stored on your DVDs.
Do I have a DVD Decoder
One way to check if you have a DVD decoder is to use the “dvdupgrd” program that comes with Windows. This program will detect if you have a DVD Decoder installed and let you know if there is an upgrade available. To do so, click on the Start menu and select Run or press the Windows and the R key to open the Run dialog window. In the Open text box type: dvdupgrd /detect and hit Enter or click OK. A window will open displaying the name of the detected decoder and the version that is installed. At the bottom of the window you will see a W2k Upgrade and a Win9x Upgrade field with either a Yes or a No letting you know whether an upgrade is available. If an upgrade is available, you can click the Start menu, select Run (or hit the Windows and the R key) to bring up the Run dialog window, type dvdupgrd /upgrade in the Open text box, and then press Enter or click OK. You will be sent to the website of the DVD decoder’s manufacturer where you can follow the instructions to get the latest version of the decoder installed. The dvdupgrd program will return a window that says “No Decoders found” if you do not have a Microsoft certified DVD decoder installed and will have to obtain one.
Installing a DVD Decoder
There are several commercially available DVD decoders from ATI, Cyberlink, Intervideo, Nvidia and Ravisent. They range in price from $15.00 USD to $49.95 USD. There is also a free alternative that is available in the K-Lite Codec Pack. The K-Lite codec pack is a user friendly collection of freely available audio and video decoders. There are 5 different variants of the K-lite codec pack: Basic, Standard, Full, Mega, Corporate, and 64-Bit. The Standard Edition is the lightest variant that includes a DVD decoder. Even though MPEG-2 is a standard compression format, there are many ways for it to be decoded. Each decoder, whether free or commercial, accomplishes the decoding in its own way. Some decoders may tax your CPU more than others, some will take advantage of the hardware acceleration of modern graphics cards, and there are image quality differences between the different decoders as well. Download the K-Lite Codec Pack Standard Variant or purchase a decoder from one of the aforementioned vendors, install it and you will be able to play DVDs in Windows Media Player. Simply launch Windows Media Player, click Play → DVD, VCD, or CD Audio, make sure the DVD is inserted, and select your DVD drive. The disc should start playing.